Time: 736 AM Mon August 17, 2020 Forecaster: Justin Brooks

Heavy Precipitation Outlook
Flash Flood Prediction Program

ANOTHER HOT AND HAZY DAY WITH A VERY SLIGHT CHANCE FOR AN ISOLATED HIGH-BASED THUNDERSTORM
-Upper-level flow has shifted more N/NW which will keep similar conditions in place today. Hot and hazy as high temperatures remain in the 90's on the plains with mid to upper 80's along the foothills.
-A weak disturbance will move in from the NW this afternoon which could trigger some weak storm development over the District, however, isolated thunderstorms today will be high-based with minimal, if any precipitation reaching the ground. 90 degree temperatures with low 40's dew points suggest that any storms that do develop can produce very gusty winds with gusts up to 50mph along with dry lightning.
-Skies will gradually clear by sunset as low temperatures drop into the 60's overnight.
STORM RAINFALL POTENTIAL AND DURATION: Very isolated rain showers and weak thunderstorms will have the potential to produce a trace to 0.1" of rain. Supplemental QPF is available at https://qpf.udfcd.org

WORST CASE SCENARIO: A moderate thunderstorm, if able to develop, will have the potential to produce 0.1-0.3" of rain in 10-30 minutes.

A LOOK AHEAD: Hot, hazy and generally dry conditions will continue Tuesday as high-pressure continues to churn towards the west. A possible reprieve from dry conditions heading into the weekend as a bit more upper-level moisture moves in bringing a better chance for scattered afternoon rain and isolated thunderstorms Wednesday through Friday.

Location Prime Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Arapahoe 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Boulder 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Broomfield 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Denver 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Douglas 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Jefferson 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Foothills above 6500ft      
Boulder 200 PM TO 600 PM
Trace (15%) to 0.1" (5%) to 0.3" (0%) NONE
Douglas 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
Jefferson 200 PM TO 600 PM
Trace (20%) to 0.1" (10%) to 0.3" (5%) NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.